FIREFLIES AND GLOW-WORMS AND THETR LIGHT. 191 
If the female beetle has been secured, she should be kept alive 
and placed in a likely situation, and a watch kept for the males 
coming to visit her. At the same time it is essential that careful 
notes should be made of the behaviour of the female and of the arrival 
of the male. Asan indication of what may be expected a brief ac- 
count of the habits of some of our better known species may not be 
out of place. 
Many members of the Natural History Society of Siam will no 
doubt be familiar with the common Glow-worm of our English lanes 
and hedges. The pale greenish lights may sometimes be observed in 
numbers in the grass by the roadside in June and July. At Lugano 
this summer they were noticed to be particularly partial to the walls, 
sitting sometimes 10 or 12 feet from the ground, and in this situation 
their light would be visible from a long distance. If more closely 
observed, whether sitting on the ground amongst low vegetation, or 
hanging vertically on some stem a few inches above it, the light will 
be seen streaming from the organ on the underside of the tail; the 
body is twisted first to one side then to the other, in order to expose 
the light more fully. Often I have carefully noted the position of one 
of these lights and visited the spot from time to time; at one visit the 
light has been found to have disappeared, but a careful search of the 
spot where it should be, has revealed the female beetle with one or 
more males in close attendince. Unfortunately I have never been 
able to witness the actual arrival of the male, which in this species is 
not or but very feebly luminous. 
Mr. E. G. Green (+) lras published notes on the use of the light 
of two species of Glow-worm from Ceylon. In one of these, Lampro- 
phorus tenebrosus, the apterous female exhibits her light much as does 
our Glow-worm; the male, though normally brilliant, approaches a 
“calling” female with the light shut off, its advent being heralded 
only by the partial extinction of the light of the female. In the 
other, Dioptoma adamsi, the larviform female was observed to recurve 
the body over the back so as to exhibit the ventral subtermmfnal light 
organ. On the approach of the male, the light was partially eclipsed 
and the tail turned down. The male at the time was not known to be 
luminous, but under the stimulus of sexual excitement it was ob- 
served to exhibit luminous spots along the sides of the abdomen 
(1) Trans, Eat. Soc. 1912, p. 717. 
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